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The GERDA collaboration is performing a search for neutrinoless double beta decay of 76 Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R&D phase.

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Two cylindrical forward TPC detectors are described which were constructed to extend the phase space coverage of the STAR experiment to the region 2.5 < |η| < 4.0. For optimal use of the available space and in order to cope with the high track density of central Au+Au collisions at RHIC, a novel design was developed using radial drift in a low diffusion gas. From prototype measurements a 2-track resolution of 1 -2 mm is expected.

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The Belle II experiment at the Super Flavour Factory SuperKEKB in Tsukuba, Japan, has started regular operation with its final detector setup in spring 2019. The Belle II vertexing system consists of four layers of double sided silicon strips (SVD) and two layers of DEPFET pixel sensors (PXD). These inner most pixel layers are arranged at radii of 14 mm and 22 mm around the beam pipe. The sensors with pixel sizes down to 50 µm × 55 µm are thinned down to 75 µm thickness to minimize multiple scattering. They are most crucial for reconstructing the secondary decay vertices of short lived B and D mesons with a precision of better than 15 microns. The high luminosity and harsh background conditions impose challenges on the operation of the detector close to the interaction point.

This article is published by the Physical Society of Japan under the terms of the Creative Commons Attribution 4.0 License. Any further distribution of this workThe Belle II experiment at the super KEK B factory (SuperKEKB) started its physics operation with the full detector setup in March 2019, and it aims at collecting 50 ab −1 of e + e − collision data. The vertex detector (VXD) of Belle II contains a 4-layer silicon vertex detector (SVD) using double sided silicon strips and an inner 2-layer pixel detector (PXD) that is based on the depleted P-channel Field Effect Transistor (DEPFET) technology. The signal generation and amplification are combined in pixels with a minimum pitch of 55 µm × 50 µm. The sensors are thinned down to 75 µm, and each module has interconnects and ASICs integrated on the sensor with silicon frames for mechanical support. This approach led to a material budget of around 0.21% X 0 per layer including the cooling structure in the acceptance region. The PXD has an integration time of around 20 µs, a signal-tonoise ratio of around 50 and a detecting efficiency of better than 99%. Its two layers are arranged at the radii of 14 mm and 22 mm around the interaction point, and an impact parameter resolution of better than 15 µm has been achieved. Due to its close proximity to the beam line and its sensitivity to few-keV photons, the PXD also plays an important role in background studies.